main: add "go doc" package comment

Should show up on https://pkg.go.dev/github.com/rfjakob/gocryptfs?tab=doc
which currently reads "No documentation available for this package!"

1 files changed, 3 insertions, 0 deletions

diff --git a/main.go b/main.go
index f81174b..1a741ed 100644
--- a/main.go
+++ b/main.go
@@ -1,3 +1,6 @@
+// gocryptfs is an encrypted overlay filesystem written in Go.
+// See README.md ( https://github.com/rfjakob/gocryptfs/blob/master/README.md )
+// and the official website ( https://nuetzlich.net/gocryptfs/ ) for details.
 package main
 
 import (